The present invention relates to a polymerizable organic composition. More particularly, the present invention relates to a polymerizable composition comprising a polyol(allyl carbonate) monomer and a block copolymeric polyether additive that is free of radically polymerizable ethylenically unsaturated groups. The present invention relates also to polymerizates, e.g., lenses, obtained from said compositions.
Polymerizable organic compositions based on polyol(allyl carbonate), particularly diethylene glycol bis(allyl carbonate), and polymerizates obtained therefrom are well known in the art. Polymerizates of polymerizable organic compositions based on homopolymers of diethylene glycol bis(allyl carbonate) possess excellent clarity, good flexibility and abrasion resistance. Examples of applications for which such polymerizates may be used include, ophthalmic lenses, sunglasses, and automotive and aircraft transparencies. It has been observed that tinting of polymerizates prepared from such compositions by surface impregnation of dyes can, in certain instances, result in an uneven tinting of the surface. Such uneven tinting is referred to as tinting failure.
When tinting failure occurs, it is often manifested as visually observable defects on the tinted surface(s) of the polymerizate, which are commonly referred to as xe2x80x9cfernsxe2x80x9d or xe2x80x9cmoons.xe2x80x9d In the case of tinted ophthalmic lenses, such as tinted ophthalmic lenses having a positive diopter, i.e., plus lenses, and non-corrective lenses, e.g., sunglasses, such tinting failure often results in rejection and scrapping of the tinted lens. A solution to tinting failure is desirable in order to avoid the economic loss that results from the scrapping of lenses having tinting defects.
U.S. Pat. No. 5,973,093 describes polymerizable organic compositions of a major amount of polyol(allyl carbonate) and from about 2 to 35 weight percent of an alkoxylated bisphenol having acrylate or methacrylate groups. The polymerizable compositions of the ""093 patent are also described as optionally comprising from 0.05 to 15 weight percent of a flexibilizing additive having no radically polymerizable groups, such as allyl or methacryloyl groups.
European Patent Application No. EP 903,217 A2 describes a cast-molding material for a plastic lens which is almost free from causing defective dyeing when dyed. The cast-molding material of the EP 903,217 application is described as containing a combination of diethylene glycol bis(allyl carbonate) and a polyether-modified silicone compound.
U.S. Pat. No. 4,374,745 describes an aqueous or gel cleaning composition which comprises from 0.02 to 25 percent by weight of at least one nonionic cleaner, e.g., oxyethylene oxypropylene polymers, from 0.01 to 10 percent by weight of a diglycol carbonate monomer, e.g., diethylene glycol bis(allyl carbonate), and the balance being water. The cleaning compositions of the ""745 patent are described as being especially suitable for cleaning glass and plastic lenses and eyeglass frames.
U.S. Pat. No. 4,310,330 describes a method for the manufacture of a colored nonfogging article, which comprises bringing a nonfogging substrate containing surfactant into contact with a dyeing solution containing a surfactant, a solvent and a coloring material. The nonfogging substrate of the ""330 patent is described as an article of plastic material or glass which has its surface coated with a film made of a nonfogging resin containing a surfactant.
It has now been discovered that cured polymerizates prepared from the polymerizable compositions of the present invention are substantially free of tinting defects, for example, tinting defects referred to in the art as ferns or moons. In accordance with the present invention there is provided a polymerizable composition comprising:
(a) a radically polymerizable monomer represented by the following general formula I,
Rxe2x80x94[xe2x80x94Oxe2x80x94C(O)xe2x80x94Oxe2x80x94R1]ixe2x80x83xe2x80x83I
xe2x80x83wherein R is a polyvalent residue of a polyol having at least two hydroxy groups, R1 is an allyl group, and i is a whole number from 2 to 4; and
(b) an additive represented by the following general formula II,
R2xe2x80x94O"Parenopenst"R3O"Parenclosest"x"Parenopenst"R4O"Parenclosest"y"Parenopenst"R5O"Parenclosest"zR6xe2x80x83xe2x80x83II
xe2x80x83wherein R2 and R6 are each selected independently from hydrogen, Cl-C20 (e.g., C1-C6or C1-C4) linear or branched alkyl, cycloalkyl having from 5 to 7 carbon atoms in the cyclic ring, aryl (e.g., phenyl or benzyl), C2-C20 (e.g., C2-C4) linear or branched saturated or unsaturated alkanoyl, saturated or unsaturated cycloalkanoyl having from 5 to 7 carbon atoms in the cyclic ring and aroyl (e.g., benzoyl), R2 and R6 each being free of radically polymerizable ethylenically unsaturated groups; R3O and R5O are the same or different; R4O is different than each of R3O and R5O; R3O, R4O and R5O are each independently a divalent residue of an epoxide; x and z are each independently a number from 0 to 200, provided that the sum of x and z is greater than zero; and y is a number from 3 to 200. Additive (b) is present in the composition of the present invention in an amount at least sufficient such that a polymerizate of the composition is substantially free of tinting defects, such as ferns and moons.
The features that characterize the present invention are pointed out with particularity in the claims, which are annexed to and form a part of this disclosure. These and other features of the invention, its operating advantages and the specific objects obtained by its use will be more fully understood from the following detailed description and the accompanying illustrative drawing.
Other than in the operating examples, or where otherwise indicated, all numbers expressing quantities of ingredients, reaction conditions, etc. used in the specification and claims are to be understood as modified in all instances by the term xe2x80x9cabout.xe2x80x9d